1. Field of the Invention
The present invention relates to an electrical connector, particularly to a structure of an electrical connector adapted for use in a card medium such as an IC card, etc. having connecting terminals for electrically connecting to an external device.
2. Description of the Related Art
A card medium such as an IC card, etc. having connecting terminals for electrically connecting to an external device can write data in or read the data written in the IC card. Data is written and read using a card reader/writer. The card reader/writer has an electrical connector for electrically connecting to connecting terminals of the card medium. It is possible to electrically write data in the card medium or read the data from the card medium when the card medium is inserted into the card reader/writer so as to permit contacts of the electrical connector to contact the connecting terminals of the card medium. The card medium employs spring contacts as contacts so as to be fit for the frequent attachment and detachment thereof.
An electrical connector of this type is, for example, disclosed in Japanese Patent Publication No. 60-3234. A structure of this electrical connector is shown in FIG. 1.
In this prior art electrical connector, denoted at 1 is a card medium having electrical connecting terminals 2, denoted at 3 is a case having an insertion slot 3a through which the card medium 1 is inserted, denoted 4 is a clamping portion movably accommodated in the case 3 and denoted 5 is a contact attached to the clamping portion 4.
When the card medium 1 is inserted through the insertion slot 3a of the electrical connector and it is pushed toward the clamping portion 4, the clamping portion 4 is moved to the left and turned clockwise. When the clamping portion 4 is turned, the contacts 5 are lowered and connected to the connecting terminals 2 provided on the card medium 1. FIG. 2 shows a state where the contacts 5 of the electrical connector contact the corresponding connecting terminals 2 of the card medium. Since the contacts 5 have resiliency, they surely contact the connecting terminals 2 of the card medium 1 in a given pressure.
However, since the clamping portion 4 having the contacts 5 is movable in the prior art electrical connector having the aforementioned arrangement, there are the following problems. (A) The card medium 1 can not be smoothly inserted into or pulled out of the case 3 due to the friction which is generated when the clamping portion 4 is moved inside the case 3, (B) since the case 3 requires a space in which the clamping portion 4 is moved, it becomes large in a direction of inserting the card medium 1 and thick in a vertical direction, (C) since the contacts 5 are moved, it becomes complex to design the clamping portion 4 where the contacts 5 contact the corresponding connecting terminals 2 with assurance and the space where the clamping portion 4 is moved inside the case 3, (D) since the contacts 5 are moved, a method to electrically connect the contacts 5 with an internal circuit of the card reader/writer which is provided outside the case 3 becomes complex. Further, there is a problem in that (E) since the card medium 1 is inserted and pulled out in a state where the contacts 5 contact the connecting terminals 2 of the card medium 1 with a given pressure, the connecting terminals 2 of the card medium 1 are damaged.
The present invention has been made in view of the aforementioned problems, and it is an object of the invention to provide an electric connector wherein a card medium can be easily inserted and pulled out and a this case can be used. It is another object of the invention to provide an electrical connector wherein electrical connection between connecting terminals of a card medium, contacts and an internal circuit of a card reader/writer can be surely performed with a simple design. It is still another object of the invention to provide an electrical connector wherein the connecting terminals of the card medium are not damaged.